Using the Patient Portal *Please note: the patient must have an existing patient portal account ... Greenwood Pediatrics Centennial. 9094 E. Mineral Avenue, Suite #100, Centennial, CO 80112 (303) 694-3200. Greenwood Pediatrics Parker. 16830 Northgate Drive, Suite #150, Parker, CO 80134 (303) 805-7879. Greenwood Pediatrics Littleton..